{"id":{"repo_id":"waikato-masters","oai_identifier":"oai:researchcommons.waikato.ac.nz:10289/2646"},"canonical_url":"https://search.dev.ndltd.org/etd/waikato-masters/oai:researchcommons.waikato.ac.nz:10289/2646","repository":{"repo_id":"waikato-masters","name":"University Waikato","base_url":"https://researchcommons.waikato.ac.nz/server/oai/request"},"display":{"title":"Behavioural Economics: The Inferior-Good Effect","abstract":"These experiments used 15 domestic hens to investigate the inferior-good effect, a decrease in consumption of a commodity as income increases. Experiment 1 investigated plain and salted wheat to serve as superior goods (opposite to inferior goods) and inferior goods. Hens consumed mostly plain wheat when given ad-libitum access so it was the intended superior good and salted wheat was the intended inferior good. In the next experiments, 3 s of plain wheat and 10 s of salted wheat were available for single responses on 2 keys during discrete trials. Income changed by changing the inter-trial interval (ITI) of fixed-length sessions or the total number of trials. Experiment 2 partially replicated the Silberberg et al. (1987) procedure, using the ITI income analogue for 6 hens. When income increased, 4 hens sometimes responded less on the salted-wheat key (demonstrating the inferior-good effect), 2 of these hens and a 5th hen sometimes responded more on both keys but proportionally more on the plain-wheat key (termed here as a relative inferior-good effect). Experiment 3a partially replicated the Hastjarjo et al. (1990a) procedure using the total-trials analogue for 7 other hens. The inferior-good effect occurred across some conditions for 2 hens while other hens tended to respond on the plain-wheat key, suggesting lack of contingency contact. When a 60-s ITI was added in Experiment 3b, variability increased for most hens, but only 1 hen showed the effect, 1 of the hens that did so in Experiment 3b. These 6 hens' (1 died) 80% bodyweights were re-assessed in Experiment 4 and hens were below 80% during Experiments 3a and 3b, suggesting that the lack of the inferior-good effect was not due to some hens being at high weights. The ITI analogue was used for these 6 hens in Experiment 5 and the effect occurred for 2 hens. Experiment 6 added forced-choice trials to the total-trials analogue (with 60-s ITI) to guarantee contingency contact. The inferior- and/or relative-inferior-good effect occurred for 3 hens. Across Experiments 2 through 6, body weights were usually heavier in high-income conditions and a within-session pattern of early-salted-late-plain responding occasionally occurred. Crop capacities of 5 Experiment-2 hens and a new hen (1 died) were assessed in Experiment 7 and there was no relation between this measure and inferior-or relative-inferior-good effects. Experiments 8 and 9 examined effects of pre- and post-feed in low-income conditions using the ITI analogue. When hens were pre-fed, responding for 5 of 7 hens resembled responding in high-income conditions of Experiment 2 with more plain-wheat responding and similar or less salted-wheat responding in some conditions (behaviour similar to the inferior- and relative-inferior-good effects, but without the income change). A similar pattern was found for 4 of 5 hens when hens were post-fed in Experiment 9, suggesting that food in the digestive tract may have played a role, and perhaps not the income manipulations themselves, where it (or other component of body weight) may have abolished quantity (i.e., the intended-inferior-good) as a reinforcer. Although these experiments occasionally demonstrated inferior- and relative-inferior-good effects, but less convincingly than published studies, the effects of income may have been non-specific. The usefulness of the inferior-good concept and other income-related economic concepts are thus challenged.","abstract_html":"These experiments used 15 domestic hens to investigate the inferior-good effect, a decrease in consumption of a commodity as income increases. Experiment 1 investigated plain and salted wheat to serve as superior goods (opposite to inferior goods) and inferior goods. Hens consumed mostly plain wheat when given ad-libitum access so it was the intended superior good and salted wheat was the intended inferior good. In the next experiments, 3 s of plain wheat and 10 s of salted wheat were available for single responses on 2 keys during discrete trials. Income changed by changing the inter-trial interval (ITI) of fixed-length sessions or the total number of trials. Experiment 2 partially replicated the Silberberg et al. (1987) procedure, using the ITI income analogue for 6 hens. When income increased, 4 hens sometimes responded less on the salted-wheat key (demonstrating the inferior-good effect), 2 of these hens and a 5th hen sometimes responded more on both keys but proportionally more on the plain-wheat key (termed here as a relative inferior-good effect). Experiment 3a partially replicated the Hastjarjo et al. (1990a) procedure using the total-trials analogue for 7 other hens. The inferior-good effect occurred across some conditions for 2 hens while other hens tended to respond on the plain-wheat key, suggesting lack of contingency contact. When a 60-s ITI was added in Experiment 3b, variability increased for most hens, but only 1 hen showed the effect, 1 of the hens that did so in Experiment 3b. These 6 hens' (1 died) 80% bodyweights were re-assessed in Experiment 4 and hens were below 80% during Experiments 3a and 3b, suggesting that the lack of the inferior-good effect was not due to some hens being at high weights. The ITI analogue was used for these 6 hens in Experiment 5 and the effect occurred for 2 hens. Experiment 6 added forced-choice trials to the total-trials analogue (with 60-s ITI) to guarantee contingency contact. The inferior- and/or relative-inferior-good effect occurred for 3 hens. Across Experiments 2 through 6, body weights were usually heavier in high-income conditions and a within-session pattern of early-salted-late-plain responding occasionally occurred. Crop capacities of 5 Experiment-2 hens and a new hen (1 died) were assessed in Experiment 7 and there was no relation between this measure and inferior-or relative-inferior-good effects. Experiments 8 and 9 examined effects of pre- and post-feed in low-income conditions using the ITI analogue. When hens were pre-fed, responding for 5 of 7 hens resembled responding in high-income conditions of Experiment 2 with more plain-wheat responding and similar or less salted-wheat responding in some conditions (behaviour similar to the inferior- and relative-inferior-good effects, but without the income change). A similar pattern was found for 4 of 5 hens when hens were post-fed in Experiment 9, suggesting that food in the digestive tract may have played a role, and perhaps not the income manipulations themselves, where it (or other component of body weight) may have abolished quantity (i.e., the intended-inferior-good) as a reinforcer. Although these experiments occasionally demonstrated inferior- and relative-inferior-good effects, but less convincingly than published studies, the effects of income may have been non-specific. The usefulness of the inferior-good concept and other income-related economic concepts are thus challenged.","abstract_has_math":false,"creators":["Messick, Eric Michael"],"institution":"The University of Waikato","degree_name":null,"degree_level":null,"degree_discipline":null,"degree_department":null,"school":null,"contributors":[],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2007,"date_issued":"2007","date_published":"2007","updated_at":"2026-07-24T05:57:15Z","subjects":["behavioural economics","inferior good","income","choice","consumption","body weight","crop","gallus domesticus"],"languages":[],"rights":["All items in Research Commons are provided for private study and research purposes and are protected by copyright with all rights reserved unless otherwise indicated."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":null,"outbound_label":null,"outbound_source":null},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:creator","label":"Author","values":["Messick, Eric Michael"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.issued","label":"Date","values":["2007"]},{"key":"dc:publisher.institution","label":"Dc Publisher Institution","values":["The University of Waikato"]},{"key":"dc:relation.isreferencedby","label":"Dc Relation Isreferencedby","values":["https://hdl.handle.net/10289/2646"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["behavioural economics","inferior good","income","choice","consumption","body weight","crop","gallus domesticus"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["All items in Research Commons are provided for private study and research purposes and are protected by copyright with all rights reserved unless otherwise indicated."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.uri","label":"Identifier URI","values":["https://researchcommons.waikato.ac.nz/bitstreams/ec129ba7-974c-4389-be6b-53cd57213b26/download"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["These experiments used 15 domestic hens to investigate the inferior-good effect, a decrease in consumption of a commodity as income increases. Experiment 1 investigated plain and salted wheat to serve as superior goods (opposite to inferior goods) and inferior goods. Hens consumed mostly plain wheat when given ad-libitum access so it was the intended superior good and salted wheat was the intended inferior good. In the next experiments, 3 s of plain wheat and 10 s of salted wheat were available for single responses on 2 keys during discrete trials. Income changed by changing the inter-trial interval (ITI) of fixed-length sessions or the total number of trials. Experiment 2 partially replicated the Silberberg et al. (1987) procedure, using the ITI income analogue for 6 hens. When income increased, 4 hens sometimes responded less on the salted-wheat key (demonstrating the inferior-good effect), 2 of these hens and a 5th hen sometimes responded more on both keys but proportionally more on the plain-wheat key (termed here as a relative inferior-good effect). Experiment 3a partially replicated the Hastjarjo et al. (1990a) procedure using the total-trials analogue for 7 other hens. The inferior-good effect occurred across some conditions for 2 hens while other hens tended to respond on the plain-wheat key, suggesting lack of contingency contact. When a 60-s ITI was added in Experiment 3b, variability increased for most hens, but only 1 hen showed the effect, 1 of the hens that did so in Experiment 3b. These 6 hens' (1 died) 80% bodyweights were re-assessed in Experiment 4 and hens were below 80% during Experiments 3a and 3b, suggesting that the lack of the inferior-good effect was not due to some hens being at high weights. The ITI analogue was used for these 6 hens in Experiment 5 and the effect occurred for 2 hens. Experiment 6 added forced-choice trials to the total-trials analogue (with 60-s ITI) to guarantee contingency contact. The inferior- and/or relative-inferior-good effect occurred for 3 hens. Across Experiments 2 through 6, body weights were usually heavier in high-income conditions and a within-session pattern of early-salted-late-plain responding occasionally occurred. Crop capacities of 5 Experiment-2 hens and a new hen (1 died) were assessed in Experiment 7 and there was no relation between this measure and inferior-or relative-inferior-good effects. Experiments 8 and 9 examined effects of pre- and post-feed in low-income conditions using the ITI analogue. When hens were pre-fed, responding for 5 of 7 hens resembled responding in high-income conditions of Experiment 2 with more plain-wheat responding and similar or less salted-wheat responding in some conditions (behaviour similar to the inferior- and relative-inferior-good effects, but without the income change). A similar pattern was found for 4 of 5 hens when hens were post-fed in Experiment 9, suggesting that food in the digestive tract may have played a role, and perhaps not the income manipulations themselves, where it (or other component of body weight) may have abolished quantity (i.e., the intended-inferior-good) as a reinforcer. Although these experiments occasionally demonstrated inferior- and relative-inferior-good effects, but less convincingly than published studies, the effects of income may have been non-specific. The usefulness of the inferior-good concept and other income-related economic concepts are thus challenged."]},{"key":"dc:format.checksum.md5","label":"Dc Format Checksum Md5","values":["64c5f3a8ea2a60496ae26a3f7ac6725b","937b36a9c447c8c5a0c659eebb1e165c"]},{"key":"dc:title","label":"Title","values":["Behavioural Economics: The Inferior-Good Effect"]}]}],"canonical_facts":{"dc:creator":["Messick, Eric Michael"],"dc:date.issued":["2007"],"dc:description.abstract":["These experiments used 15 domestic hens to investigate the inferior-good effect, a decrease in consumption of a commodity as income increases. Experiment 1 investigated plain and salted wheat to serve as superior goods (opposite to inferior goods) and inferior goods. Hens consumed mostly plain wheat when given ad-libitum access so it was the intended superior good and salted wheat was the intended inferior good. In the next experiments, 3 s of plain wheat and 10 s of salted wheat were available for single responses on 2 keys during discrete trials. Income changed by changing the inter-trial interval (ITI) of fixed-length sessions or the total number of trials. Experiment 2 partially replicated the Silberberg et al. (1987) procedure, using the ITI income analogue for 6 hens. When income increased, 4 hens sometimes responded less on the salted-wheat key (demonstrating the inferior-good effect), 2 of these hens and a 5th hen sometimes responded more on both keys but proportionally more on the plain-wheat key (termed here as a relative inferior-good effect). Experiment 3a partially replicated the Hastjarjo et al. (1990a) procedure using the total-trials analogue for 7 other hens. The inferior-good effect occurred across some conditions for 2 hens while other hens tended to respond on the plain-wheat key, suggesting lack of contingency contact. When a 60-s ITI was added in Experiment 3b, variability increased for most hens, but only 1 hen showed the effect, 1 of the hens that did so in Experiment 3b. These 6 hens' (1 died) 80% bodyweights were re-assessed in Experiment 4 and hens were below 80% during Experiments 3a and 3b, suggesting that the lack of the inferior-good effect was not due to some hens being at high weights. The ITI analogue was used for these 6 hens in Experiment 5 and the effect occurred for 2 hens. Experiment 6 added forced-choice trials to the total-trials analogue (with 60-s ITI) to guarantee contingency contact. The inferior- and/or relative-inferior-good effect occurred for 3 hens. Across Experiments 2 through 6, body weights were usually heavier in high-income conditions and a within-session pattern of early-salted-late-plain responding occasionally occurred. Crop capacities of 5 Experiment-2 hens and a new hen (1 died) were assessed in Experiment 7 and there was no relation between this measure and inferior-or relative-inferior-good effects. Experiments 8 and 9 examined effects of pre- and post-feed in low-income conditions using the ITI analogue. When hens were pre-fed, responding for 5 of 7 hens resembled responding in high-income conditions of Experiment 2 with more plain-wheat responding and similar or less salted-wheat responding in some conditions (behaviour similar to the inferior- and relative-inferior-good effects, but without the income change). A similar pattern was found for 4 of 5 hens when hens were post-fed in Experiment 9, suggesting that food in the digestive tract may have played a role, and perhaps not the income manipulations themselves, where it (or other component of body weight) may have abolished quantity (i.e., the intended-inferior-good) as a reinforcer. Although these experiments occasionally demonstrated inferior- and relative-inferior-good effects, but less convincingly than published studies, the effects of income may have been non-specific. The usefulness of the inferior-good concept and other income-related economic concepts are thus challenged."],"dc:format.checksum.md5":["64c5f3a8ea2a60496ae26a3f7ac6725b","937b36a9c447c8c5a0c659eebb1e165c"],"dc:identifier.uri":["https://researchcommons.waikato.ac.nz/bitstreams/ec129ba7-974c-4389-be6b-53cd57213b26/download"],"dc:publisher.institution":["The University of Waikato"],"dc:relation.isreferencedby":["https://hdl.handle.net/10289/2646"],"dc:rights":["All items in Research Commons are provided for private study and research purposes and are protected by copyright with all rights reserved unless otherwise indicated."],"dc:subject":["behavioural economics","inferior good","income","choice","consumption","body weight","crop","gallus domesticus"],"dc:title":["Behavioural Economics: The Inferior-Good Effect"],"dc:type":["Thesis"]},"updated_at":"2026-07-24T05:57:15Z"}